Potential role of indole-3-propionic acid in tuberculosis: current perspectives and future prospects

Introduction: Indole-3-propionic acid (IPA), a tryptophan catabolite derived from gut bacterial metabolism, has been identified as a functional link between the gut microbiome and tuberculosis. Area covered: IPA has gained ample attention over the past two decades on account of its multiple physiological roles, besides being both detectable and quantifiable. IPA is well studied across different health conditions, including cardiovascular and neurological conditions. IPA blocks tryptophan synthesis in Mycobacterium by binding to the allosteric tryptophan-binding site of TrpE, thereby threatening Mycobacterium survival due to tryptophan deficit. Expert opinion: Characterizing IPA would enable its use as a tool to investigate the pathophysiology of tuberculosis. Integrating ‘OMICS’ techniques (through next-generation sequencing) along with targeted microbial metabolomics may help explore the possible association of serum IPA levels with TB in patients. This will aid in identifying IPA-producing gut microbes and selecting probiotic strains as a microbiome-targeting adjunct therapy, eventually enhancing our understanding of the molecular dynamics of the pathophysiology of tuberculosis in the context of the microbiome.